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1 Original Article Korean J Health Promot 2010;10: pissn: eissn: 한국성인에서당뇨병진단기준으로서의공복혈당과당화혈색소비교 최은영 단국대학교의과대학가정의학과 Comparison of Fasting Glucose and Hemoglobin A 1c for Diagnosing Diabetes in Korean Adults Eun Young Choi Department of Family Medicine, Dankook University College of Medicine, Cheonan, Korea Background: This study aimed to evaluate hemoglobin A 1c (HbA 1c) level of 6.5% as a diagnostic criterion for diabetes mellitus (diabetes) compared with fasting glucose level of 126 mg/dl, and to compare the characteristics of the individuals diagnosed with diabetes by each of HbA 1c and fasting glucose. Methods: Data from the 1998 Korean National Health and Nutrition Examination Survey were used. Analyses were done for 4,875 adults ( 20 years) without a self-reported history of diabetes and anemia and had fasted for at least 8 hours and had the HbA 1c level done. Results: Of the 4,875 adults, 1.4% had HbA 1c 6.5% and fasting glucose 126 mg/dl, 0.4% had HbA 1c 6.5% and fasting glucose <126 mg/dl, and 5.6% had HbA 1c <6.5% and fasting glucose 126 mg/dl. The pre- valence of diabetes was 7.0% by fasting glucose and 1.8% by HbA 1c, which underestimated the prevalence of diabetes compared with fasting glucose. After adjusting for age, sex, smoking status, and BMI, individuals with concordant diabetes by both fasting glucose and HbA 1c had higher fasting glucose, HbA 1c, and waist circumference (P<0.05), and higher odds ratio for metabolic syndrome (OR=2.6, 95% confidence interval, , P<0.01) compared with those with discordant diabetes. Conclusions: In Korean adults, HbA 1c level of 6.5% as a diagnostic criterion was less sensitive in detecting newly diagnosed diabetes defined by fasting glucose. There was a significant difference in the odds ratio for metabolic syndrome between individuals with concordant and discordant diabetes defined by fasting glucose and HbA 1c. Korean J Health Promot 2010;10(4): Keywords: Diabetes mellitus, Hemoglobin A 1c, Fasting glucose, Diagnosis, Metabolic syndrome 서 론 당화혈색소는 2-3개월동안의혈당을반영하는수치로당뇨병의조절정도를파악하기위해시행하고있는검사이다. 당화혈색소는공복상태와관계없이측정이가능하 Received:August 6, 2010 Accepted:November 3, 2010 Corresponding author:eun Young Choi, MD Department of Family Medicine, Dankook University College of Medicine, San 16-5, Anseo-dong, Dongnam-gu, Cheonan , Korea Tel: , Fax: choiey@dku.edu 이연구는 2008 학년도단국대학교대학연구비의지원으로연구되었음. 고, 순간혈당보다스트레스나감염등의영향을덜받으며, 개인내편차가적다는장점이있다. 1) 당화혈색소는당뇨병의발생과미세혈관합병증을잘예측하는데, 2,3) 순간혈당보다당뇨병성망막병증과의상관성이더크고, 4,5) 당화혈색소 6~7% 부터는망막병증이증가하는것으로밝혀져공복혈당을대체하는당뇨병의진단도구로사용하자는주장이있었다. 6) 그러나, 당화혈색소검사방법이표준화되어있지않아당뇨병의진단에사용되지못하다가최근검사방법이표준화되면서 2009년미국당뇨병학회의국제전문가위원회에서당화혈색소 6.5% 이상을당뇨병의진단기준중하나로사용할것을권고하였으며, 1) 2010년부

2 Eun Young Choi. Comparison of Fasting Glucose and Hemoglobin A 1c for Diagnosing Diabetes in Korean Adults 163 터는당화혈색소 6.5% 이상이당뇨병진단기준의하나로추가되었다. 3) 공복혈당과당화혈색소는혈당대사의서로다른측면을반영하는검사이므로진단기준에따라당뇨병의유병률이달라질수있으며, 당뇨병으로진단되는대상자들의특성에도차이가생길수있다. 7) 또한, 당화혈색소는연령이나혈색소의생존기간, 인종에따른영향을받는것으로알려져있어서양인을대상으로마련한이기준을한국인에게그대로적용할수있을지논란의여지가있다. 1) 당뇨병을진단하는당화혈색소의절단값을조사한기존의국내연구들이있지만, 8-10) 대상이병원을방문한고위험군으로한정되어있어이를일반화하기는어렵다. 더욱이진단기준으로서의당화혈색소와공복혈당을비교하거나각각의기준에따라당뇨병으로진단된대상자들을연구한논문은국내에서전무하다. 따라서, 본연구는 1998년시행된전국민건강영양조사를사용하여 1) 기존의당뇨병진단기준인공복혈당 126 mg/dl 과새로운진단기준인당화혈색소 6.5% 를비교하여당뇨병진단기준으로서당화혈색소의적절성을평가하고, 2) 공복혈당과당화혈색소를기준으로진단된당뇨병환자의인구사회학적대사적특성을비교하고자시행하였다. 1. 대상자 방 법 본연구는 1998년 11월 1일에서 12월 30일까지시행된국민건강영양조사자료를이용하였다. 건강검진을시행한 20세이상의성인 7,962명중에서당화혈색소값이결측인 1,472명, 지난 1년간당뇨병으로약물복용중이거나진단받은 337명, 8시간이상금식하지않은 789명, 빈혈이있는 487명, 그리고혈청크레아티닌수치가 2.0 이상인 2 명을제외한 4,875명을대상으로분석을시행하였다. WA Baum Co Inc., New York, USA) 로 2번측정하였으며, 2번측정값의평균을분석에서사용하였다. 혈액은정맥에서 cc 정도를채취하여원심분리기를이용하여혈청분리관으로분리하고, 즉시냉장포장하여중앙으로운송한후분석하였다. 혈당및고밀도지단백 (HDL) 콜레스테롤, 중성지방은 Hitachi-747 자동분석기 (Hitachi Electronics, Japan) 를사용하여분석하였으며, 당화혈색소는 HLC-723G7 (Tosoh, Tokyo, Japan) 을이용하여양이온교환수지크로마토그래피법 (high performance liquid chromatography) 을사용하여분석하였다. 3. 정의 담배를전혀피우지않거나, 과거에흡연을했다고응답한사람을비흡연자로, 현재흡연을하고있다고응답한사람을흡연자로정의하였다 년미국당뇨병협회에서제시하는기준에따라공복혈당기준으로는 126 mg/dl 이상을, 당화혈색소기준으로는 6.5% 이상을당뇨병으로진단하였다. 3) 대사증후군의정의는 2001년새로개정된제 3차콜레스테롤관리지침 (The Third National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults, NCEPT- ATPⅢ) 과국제당뇨병협회 (International Diabetes Federation) 의공복혈당기준을따랐으며, 2,3) 허리둘레는한국기준을따랐다. 4) 구체적인기준은아래와같으며, 5가지기준중 3가지이상을만족할때대사증후군으로정의하였다. 1) 고혈압 : 수축기혈압 130 mmhg 혹은이완기혈압 85 mmhg 이거나고혈압약물을복용시, 2) 복부비만 : 허리둘레가남성 90 cm, 여성 85 cm, 3) 내당능장애 : 공복혈당 100 mg/dl 4) 고중성지방혈증 : 중성지방 150 mg/dl 5) HDL 콜레스테롤저하 : 남성 <40 mg/dl, 여성 <50 mg/dl 2. 측정방법 4. 통계 체중은겉옷을탈의한후얇은가운을입힌채로체중계 (Giant 150N; HANA Co Ltd., Seoul, Korea) 로 0.1 kg 단위까지측정하였다. 신장은신발을벗고신장계 (850-2,060 mm; Holtain Ltd., Crymych, United Kingdom) 로 0.1 cm 단위까지측정하였으며, 체질량지수는 kg/m 2 로계산하였다. 허리둘레는줄자를이용하여가장낮은늑골과장골능선사이를지면과수평으로 0.1 cm 단위까지측정하였다. 혈압은 5분간안정후앉은상태에서수은혈압계 (Baumanometer; 모든측정값은연속변수인경우평균과표준편차를, 명목변수의경우빈도 로표시하였다. 당화혈색소 6.5% 와공복혈당 126 mg/dl 기준에따라당화혈색소와공복혈당모두정상인군, 당화혈색소와공복혈당기준모두당뇨병인군, 당화혈색소와공복혈당기준이서로일치하지않는군으로분류하였다. 각군별인구사회학적요인과대사위험요인의차이는이산변수인경우는 χ 2 test를사용하였다. 연속변수의경우는정규분포를취하지않아로그

3 164 Korean J Health Promot Vol. 10, No. 4, 2010 변환후다중회귀분석으로각군별평균의차이를분석하였고, post-hoc 분석으로는 Bonferroni의다중비교를사용하였다. 당뇨병진단기준으로서공복혈당과당화혈색소기준의일치도는 κ statistics를사용하였으며, 공복혈당으로진단된당뇨병을예측하는당화혈색소의절단값은 receiver operating characteristics ( 이하 ROC) curve를이용하여분석하였다. 통계분석패키지로는 SPSS 18.0 (SPSS Inc., Chicago, IL, USA) 을사용하였으며, P 값이 0.05 미만일때통계적으로유의한것으로판단하였다. 결과 1. 당화혈색소와공복혈당기준에따른당뇨병의유병률 전체대상자 4,875명중당화혈색소 6.5% 이면서공복혈당 126 mg/dl인대상자가 1.4%, 당화혈색소 6.5% 이 면서공복혈당 <126 mg/dl 인대상자가 0.4%, 당화혈색소 <6.5% 이면서공복혈당 126 mg/dl 인대상자는 5.6% 였다. 새롭게진단된당뇨병의유병률을공복혈당과당화혈색소기준을모두적용하여두기준중최소한한가지이상을만족하는대상은 7.4% 였다. 그러나공복혈당만을기준으로할때당뇨병유병률이 7.0% 이므로당화혈색소기준을적용함으로써얻는유병률증가는 0.4% 로추정되었다. 새롭게진단된당뇨병의유병률은당화혈색소기준으로는 1.8% 로당화혈색소는공복혈당에비해당뇨병의유병률을 73% 과소평가하였다. 당화혈색소와공복혈당두기준간의 Kappa 값은 0.37 (95% 신뢰구간, ) 로일치도는낮았다. 2. 당화혈색소와공복혈당기준에따라분류한대상자의인구사회학적요인과대사위험요인비교 당화혈색소 6.5% 와공복혈당 126 mg/dl 기준에따라 Table 1. Characteristics of participants according to concordance of both fasting glucose and hemoglobin A 1c * Normal Discordant diabetes Concordant diabetes P Value N, % 4,509 (92.6) 298 ( 6.0) 70 ( 1.4) Female, % 2,432 (53.9) 115 (41.9) 39 (54.3) <0.001 Age, y 48.1± ± ±1.6 <0.001 Weight, kg 61.6± ± ±1.2 <0.001 Height, cm 162.4± ± ±0.9 >0.05 BMI, kg/m ± ± ±0.4 <0.001 Waist circumference, cm 81.8± ± ±0.6 <0.001 Smoking status, (n=4,750) <0.001 Nonsmoker 2,935 (66.7) 152 (53.3) 48 (71.6) Smoker 1,463 (33.3) 133 (46.7) 19 (28.4) Residence >0.05 Province 1,829 (40.6) 126 (42.6) 19 (27.1) City 2,680 (59.4) 170 (57.4) 51 (72.9) Education >0.05 Elementary 1,676 (37.2) 122 (41.2) 31 (44.3) Middle school 755 (16.7) 55 (18.6) 13 (18.6) High school 1,399 (31.0) 82 (27.7) 14 (20.0) University 679 (15.1) 34 (12.5) 12 (17.1) SBP, mmhg, (n=4,869) 127.5± ± ±2.2 <0.001 DBP, mmhg, (n=4,869) 80.3± ± ±1.4 >0.05 AST, IU/l 29.4± ± ±2.7 <0.01 ALT, IU/l 29.3± ± ±2.5 <0.001 Triglycerides, mg/dl 129.5± ± ±7.1 <0.001 HDL cholesterol, mg/dl 49.3± ± ±1.5 >0.05 FG, mg/dl 95.3± ± ±2.0 <0.001 HbA 1c, % 5.0± ± ±0.1 <0.001 Metabolic risk numbers, (n=4,869) 1.6± ± ±0.1 <0.001 Metabolic syndrome, (n=4,869) 962 (21.4) 142 (48.1) 48 (68.6) <0.001 Abbreviations: SBP, systolic blood pressure; DBP, diastolic blood pressure; AST, aspartate aminotransferase; ALT, alanine aminotransferase; HDL cholesterol, high-density lipoprotein cholesterol; FG, fasting glucose; HbA 1C, hemoglobin A 1C. * Data are presented as age-, sex-, smoking status-, and BMI-adjusted means±sd or No. unless otherwise indicated. HbA 1c <6.5 and FBS 126 mg/dl and HbA 1c 6.5 and FBS <126 mg/dl. P using a multiple linear regression for log-transformed continuous variables and χ 2 test for categorical variables. P<0.05 compared with individuals with HbA 1c <6.5 and FBS <126 mg/dl. P<0.05 compared with individuals with HbA 1c 6.5 and FBS 126 mg/dl.

4 Eun Young Choi. Comparison of Fasting Glucose and Hemoglobin A 1c for Diagnosing Diabetes in Korean Adults 165 Table 2. Adjusted odds ratios * for metabolic syndrome according to concordance of both fasting glucose and hemoglobin A 1c Characteristics OR (95% CI) β SE P Value Normal 1 Discordant diabetes 2.8 ( ) <0.001 Concordant diabetes 8.0 ( ) <0.001 Abbreviation: CI, confidence interval. Adjusted for age, sex, smoking status, and BMI. 는군에서 2.8 (95% CI, , P<0.001), 당뇨병군에서 8.0 (95% CI, , P<0.001) 으로유의하게증가하였다 ( 표 2). 두기준이서로일치하지않는군과비교시당뇨병군에서대사증후군오즈비는 2.6 (95% CI, , P<0.01) 으로통계적으로유의하게증가하였다. 3. 당뇨병진단을위한당화혈색소의절단값 1-Specificity Figure 1. Receiver operating characteristics curve for HbA 1c in assessing newly diagnosed diabetes defined by fasting glucose 126 mg/dl 한국인에서당뇨병진단을위한당화혈색소의절단값은 5.3%( 민감도 66.7%, 특이도 79.3%, AUC 0.730) 로미국당뇨병협회의기준 6.5% 보다낮았다 (Figure 1). 표3은당화혈색소절단값에따른민감도와특이도, 양성예측도와음성예측도를나타낸것으로당화혈색소절단값이낮아질수록민감도는증가하였으나, 특이도는감소하였다. 당화혈색소와공복혈당모두정상인군, 당화혈색소와공복혈당기준모두당뇨병인군, 당화혈색소와공복혈당기준이서로일치하지않는군으로분류하여인구사회학적요인과대사위험요인을비교하였다. 교육수준, 수입및거주지역 ( 도시, 시골 ) 에따른세군간의유의한차이는관찰되지않았다 (P>0.05). 여성의비율은진단기준이일치하지않는군 (41.9%) 이정상군 (53.9%) 이나당뇨병군 (54.3%) 에비해유의하게적었으며 (P<0.001), 흡연자의비율도진단기준이일치하지않는군 (46.7%) 에서정상군 (33.3%) 이나당뇨병군 (28.4%) 에비해유의하게높았다 (P<0.001) (Table 1). 성, 연령, 흡연상태, 체질량지수를보정한상태에서당뇨병군및진단기준이일치하지않는군에서의연령, 체중, 체질량지수, 허리둘레, AST, ALT, 중성지방, 공복혈당, 당화혈색소는정상군보다통계적으로유의하게더높았다 (P<0.05). 성, 연령, 흡연상태, 체질량지수를보정한후에도공복혈당과당화혈색소기준이당뇨병으로일치했던군은두기준이서로일치하지않는군에비해당화혈색소와공복혈당및허리둘레가통계적으로유의하게더증가하였다 (P<0.05) (Table 1). 대사증후군의유병률은정상군 (21.4%) 과비교시두기준이서로일치하지않는군 (48.1%) 과당뇨병군 (68.6%) 에서유의하게증가하였다 (P<0.001). 성, 연령, 흡연상태, 체질량지수를보정한상태에서정상군과비교한대사증후군의오즈비는두기준이서로일치하지않 토 론 본연구에서새롭게진단된당뇨병의유병률은공복혈당기준으로 7.0%( 남자 8.4%, 여자 5.9%), 당화혈색소기준으로는 1.9%( 남자 2.0%, 여자 1.8%) 로당화혈색소는공복혈당에비해당뇨병의유병률을 73% 과소평가하는것으로나타났다. 이러한결과는국외에서보고된기존의연구들과일치하고있는데, 중국 Qingdao지역 2,332명의주민을대상으로경구당부하검사로당뇨병을진단한연구는당뇨병진단에있어당화혈색소의민감도를 30% 미만이라고보고하고있다. 14) 년도미국 National Health and Nutrition Examination Survey ( 이하 NHANES) 자료를이용한연구에서도새롭게진단된당뇨병의유병률은당화혈색소기준으로 1.8%, 공복혈당기준으로 2.4% 로당화혈색소가공복혈당보다당뇨병의유병률을 25% 과소평가하는것으로나타났다. 7) Insulin Resistance Atherosclerosis Study에참여한당뇨병이없는참여자 855명을대상으로경구당부하검사를시행하여당화혈색소와공복혈당, 식후 2시간혈당의진단율을비교한연구에서도당화혈색소가 32.3%, 공복혈당이 45%, 식후 2시간혈당 87% 로당화혈색소의진단율이가장낮았다. 15) 년도 NHANES 조사분석에서도당화혈색소는경구당부하검사로새롭게진단된당뇨병환자의 1/3만을진단하는것으로나타났

5 166 Korean J Health Promot Vol. 10, No. 4, 2010 Table 3. Sensitivity, specificity, positive and negative predictive values for diabetes defined by fasting glucose 126 mg/dl according to different Hemoglobin A 1c cutoff points HbA 1c Cutoff point Sensitivity Specificity Positive predictive value Negative predictive value AUC * Abbreviation: AUC, area under the curve. 다. 16) 이와는대조적으로인도의 Chennai 지역의주민을대상으로경구당부하검사를시행한연구에서는당화혈색소기준으로전체당뇨병의 78%, 공복혈당으로는 59.6% 를진단하여당화혈색소의진단율이공복혈당보다높아다른연구결과들과는차이를보였다. 17) 한국은서구에비해당뇨병의유병률이급증하고있고, 18) 당뇨병환자의급격한증가는미세혈관합병증과대혈관합병증으로연결될수있어당뇨병의조기진단과적극적인조절이무엇보다필요한시점이다. 따라서, 공복혈당보다민감도가낮은당화혈색소를진단기준으로채택함으로인해당뇨병의조기진단과치료가늦어질수있으며, 동반한고혈압이나고지혈증과같은심혈관질환의위험요인들을적절하게치료하지못함으로써당뇨병으로인한합병증의위험도함께증가할것으로예상된다. 따라서, 당화혈색소 6.5% 를한국인의당뇨진단기준으로채택하기에는무리가있으며, 이를진단기준으로채택하기위해서는당화혈색소로당뇨병을진단한군과공복혈당으로진단한군간의합병증에차이가있는지여부를조사하는전향적코호트가필요할것으로생각한다. 본연구에서는공복혈당 126 mg/dl을당뇨병으로정의했을때 ROC곡선을이용한당화혈색소의적절한절단값은 5.3% ( 민감도 66.7%, 특이도 79.3%) 로미국당뇨병학회에서권고하는기준인 6.5% 보다낮았다. 지금까지국내외의연구들은당뇨병진단을위한당화혈색소의절단값을 5.3~6.4% 까지다양하게보고하고있다. 8,9,14,17,19-21) 4년간건강검진을받은대상자들을후향적으로추적한국내의연구에서공복혈당으로정의된당뇨병의발생을예측할수있는당화혈색소의절단값을 5.35% 로보고한바있으며, 9) 병문을방문한당뇨병의고위험군을대상으로경구당부하 검사를시행하여당화혈색소의절단값을조사한국내의연구에서는당화혈색소의절단값을각각 5.95%, 8) 6.1% 10) 로보고하고있다. 이와같이당화혈색소의절단값이연구마다다양하게보고되는것은대상자의연령, 대상자의선택방법, 당화혈색소의측정방법, 당뇨병의황금기준, 비만과같은대상자들의위험요인이서로다르기때문에나온결과로생각된다. 14) 당화혈색소는인종에따른영향을받는것으로알려져있는데, Diabetes Prevention Program 에서연령, 성, 학력, 혈압, 체질량지수, 헤마토크릿과인슐린저항성을모두보정한상태에서도내당능장애가있는백인에비해내당능장애가있는흑인과히스패닉의당화혈색소가더높은것으로보고되고있다. 22) 미국 NHANES 자료를분석한연구에서도당뇨병을진단하는당화혈색소의민감도가백인에서는 58.6%, 히스패닉에서는 83.6% 로차이가있고, 특이도도백인 98.3%, 흑인 93.0% 로차이를보였다. 19) 이와같은인종간의차이는혈색소의생존과단백질의 glycation 정도가인종에따라달라지는것으로설명할수있으나, 인종에따라당뇨병진단을위해서로다른당화혈색소값을사용해야하는지에대해서는아직알려져있지않아이에관한연구가필요하다. 본연구에서대상자의 1.4% 는공복혈당과당화혈색소기준모두당뇨병으로진단이일치하였으나, 5.6% 는당화혈색소 <6.5% 이면서공복혈당 126 mg/dl 였고, 0.4% 는당화혈색소 6.5% 이면서공복혈당 <126 mg/dl 으로진단이서로일치하지않았다. Carson 등 7) 이 년까지미국 NHANES 자료를분석한연구에서도대상자의 1.8% 는당화혈색소 <6.5% 이면서공복혈당 126 mg/dl 였으며, 0.5% 는당화혈색소 6.5% 이면서공복혈당 <126 mg/dl 으로진단명이일치하지않았다. 당뇨병의진단방법

6 Eun Young Choi. Comparison of Fasting Glucose and Hemoglobin A 1c for Diagnosing Diabetes in Korean Adults 167 에따른진단명의차이는두가지검사방법이혈당의서로다른생리학적면을반영할뿐아니라두검사가혈당을반영하는시간에차이가있기때문으로추측된다. 3) 당화혈색소와공복혈당두가지진단기준에따라다르게분류되는환자들의특성에대해서는아직잘알려져있지않은데, Carson 등 7) 의연구에서는당화혈색소 6.5% 이면서공복혈당 <126 mg/dl 인군이당화혈색소 <6.5% 이면서공복혈당 126 mg/dl 인군보다나이가적고, 흑인이많았으며, 혈색소가낮고 C-반응성단백값이더높은것으로나타났다. 본연구에서는성, 연령, 흡연상태, 체질량지수를보정한후에도공복혈당과당화혈색소기준이당뇨병으로일치했던당뇨병군은두기준이서로일치하지않는군에비해당화혈색소와혈당이더높았고 (P<0.05), 허리둘레가더컸다 (P<0.05). 본연구에서는당화혈색소 6.5% 이면서공복혈당 <126 mg/dl인대상자의수가 21명 (0.4%) 으로너무적어이를따로구분하지않고진단이서로일치하지않는군으로분류하여당화혈색소 <6.5% 이면서공복혈당 126 mg/dl인대상자들과함께분석하였다. 따라서진단이일치하지않는군을독립적인두군으로분리하여차이를평가하지못했는데, 향후더많은인구를대상으로공복혈당과당화혈색소로진단되는당뇨병환자들의인구사회학적및대사적차이에관한연구가진행되어야할것이다. 본연구의장점은국민건강영양조사자료를분석하였기때문에기존의국내연구들이병원을방문한당뇨병고위험군을대상으로하여연구결과를일반화하지못하는단점을극복했다는데있다. 또한, 빈혈이나크레아티닌수치가높은대상자들을제외하여이러한질병이당화혈색소에영향을미치는영향을최소화할수있었으며, 8시간이상공복상태를유지한사람을대상으로분석을시행하여당뇨병진단의정확성을높였다는장점이있다. 본연구의제한점으로는첫째, 당뇨병의진단방법으로경구당부하검사대신공복혈당을이용하였는데, 식후 2시간혈당이공복혈당보다당뇨병진단에더민감한검사로알려져있어당뇨병의유병률을과소평가했을가능성이있다. 23) 기존의국내연구에서는병원을방문한당뇨병고위험군을대상으로경구당부하검사로당뇨병을진단받았을때이중 44.3% 는공복혈당은정상이고식후 2시간혈당만높았다고보고하고있으며, 10) 60세이상의노인을대상으로경구당부하검사로당뇨병을진단한 Choi 등 24) 의연구에서도남성의 65.2%, 여성의 64.4% 은식후2 시간혈당만높았다고보고하고있다. 본연구에서경구당부하검사를시행할때당뇨병으로추가로진단될수있는대상자들은주로공복혈당 <126 mg/dl 이고당화혈색소 <6.5% 인정상군 (92.6%) 과공복혈당 <126 mg/dl이고당화혈색소 6.5% 인 군 (0.4%) 에분포하고있을것으로예상된다. 따라서, 당뇨병을진단하는당화혈색소의민감도는더감소할수있어본연구결과와상반되는결과가나오지는않을것으로생각한다. 둘째, 본연구는 1998년도국민건강영양조사자료를이용한연구로최근급증하고있는당뇨병의유병률을반영하지못했다는제한점이있다. 그러나, 유병률증가가진단검사의민감도와특이도에영향을미치지못하기때문에당화혈색소의절단값에는영향을미치지못하였을것으로생각한다. 결론적으로, 당화혈색소 6.5% 기준은공복혈당 126 mg/dl 보다당뇨병의유병률을과소평가하는것으로나타났다. 따라서, 이를진단기준으로채택할경우당뇨병진단의지연으로인한당뇨병합병증증가가예상되므로당뇨병의진단기준으로채택하기는어려울것으로생각한다. 공복혈당과당화혈색소기준이당뇨병으로일치했던군은일치하지않는군에비해허리둘레와대사증후군의위험이유의하게더컸는데, 다양한인구집단을대상으로당뇨병의진단기준에따른인구사회학적및대사적차이에관한연구들이시행되어야할것이다. 요약 연구배경 : 본연구는한국인을대상으로당뇨병진단기준인공복혈당 126 mg/dl과당화혈색소 6.5% 를비교하여당뇨병진단기준으로서당화혈색소의적절성을평가하고, 공복혈당과당화혈색소를기준으로진단된당뇨병환자의특성을비교하였다. 방법 : 1998년국민건강영양조사에서건강검진을시행한 7,962명중공복당화혈색소검사를시행하고, 당뇨병진단을받은적이없으며, 빈혈이없고, 혈중크레아티닌농도가 2 미만인대상자 4,875 명을대상으로분석을시행하였다. 결과 : 전체대상자 4,875명중당화혈색소 6.5% 이면서공복혈당 126 mg/dl인경우가 1.4%, 당화혈색소 6.5% 이면서공복혈당 <126 mg/dl인경우가 0.4%, 당화혈색소 <6.5% 이면서공복혈당 126 mg/dl 인경우가 5.6% 였다. 당뇨병의유병률은공복혈당기준 7.0%, 당화혈색소기준으로는 1.8% 였으며, 당화혈색소는공복혈당에비해당뇨병의유병률을 73% 과소평가하였다. 성, 연령, 흡연상태, 체질량지수를보정한후에도공복혈당과당화혈색소기준이당뇨병으로일치했던군은두기준이서로일치하지않았던군에비해당화혈색소와혈당및허리둘레가더컸으며 (P<0.05), 대사증후군의오즈비도 2.6 (95% CI, , P<0.01) 으로더컸다. 결론 : 한국성인에서당화혈색소 6.5% 는공복혈당으로정의한당뇨병을진단하는데민감하지않았으며, 공복혈

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DIABETES FACT SHEET IN KOREA 2012 SUMMARY About 3.2 million Korean people (10.1%) aged over 30 years or older had diabetes in 2010. Based on fasting g

DIABETES FACT SHEET IN KOREA 2012 Korean Diabetes Association (KDA) / Korea Centers for Disease Control and Prevention (CDC) DIABETES FACT SHEET IN KOREA 2012 SUMMARY About 3.2 million Korean people (10.1%)